Track ball for computer system cursor control



FIG. 1 is a top plan view of a track ball showing my new design;

FIG. 2 is a side elevational view thereof the opposite side being a mirror image thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a front elevatioanl view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a track ball for computer system cursor control, as shown and described. 